Effect of electromagnetic radiation on the Belousov-Zhabotinsky oscillating reaction

The effect of electromagnetic radiation with a frequency close to the maximum of absorption of atmospheric oxygen on the Briggs-Rauscher self-oscillating reaction is described. It is shown that the radiation intensifies oxygen production and lengthens the duration of the self-oscillating regime by more than 20%.     

Centimeter- and millimeter-wavelength matched loads based on microwave photonic crystals

Novel, small-sized broadband matched loads in the form of disordered photonic crystals containing nanometer metallic and insulating layers have been developed. It has been proposed to form insulating layers with different permittivities and low dissipation factors in both centimeter and millimeter wavelength ranges from the composites that consist of insulating matrices filled with air inclusions.     

Dynamics of nanoparticle agglomeration in a magnetic fluid in a varying magnetic field

It is found that the dependence of the magnetic nanoparticle agglomerate length in a magnetic fluid on the applied magnetic field has three characteristic segments: a substantial increase in the agglomerate length with the magnetic field in the range of weak fields, a segment with an insignificant increase in the average length of agglomerates upon an increase in the field, and a sharp increase in the agglomerate length with a further increase in the field. It is shown that the agglomerate length increases in the range of strong magnetic fields due to a decrease in the spacing between adjacent agglomerates down to their complete coalescence. The total number of agglomerates decreases thereby.     

Oligomeric oxidation products of the flavonoid quercetin

Some of the main oxidation products of quercetin were shown to be compounds formed by oligomerization of the starting flavonoid. Conditions for the preparative synthesis of these compounds were developed. Their structures were established using HPLC-MS and NMR methods. Quercetin oligomers in the natural sample, outer leaves of modified runners of Allium cepa L., were found using chromatographic procedures. The use of quercetin oligomers as indicators of its oxidation was proposed. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 344–347, July–August, 2008.     

Features of the local immobilization of NADPH-cytochrome P450 reductase and cytochrome b<Subscript>5</Subscript> on a solid surface

Using the methods of microcontact printing and atomic force microscopy, we studied a possibility of specific “protein-protein” interactions in the processes of local immobilization of cytochrome b₅ and NADPH-cytochrome P450 reductase on the surface of hydrophilic silicone. It is shown that the formation of protein complexes is possible only at a certain orientation of the molecules defined by the sequence of adsorption of biopolymers.     

Thermal stability of carboxylate salts

A correlation between the temperatures of the maximum thermal decomposition rate of salts or of the maximum heat effects, and the standard heats of formation of the respective metal oxides has been established.

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Measurements of the nanovibration amplitude by a frequency-modulated laser autodyne

A method to measure the reflector nanovibration amplitudes from the low-frequency spectrum of a signal from a frequency-modulated laser autodyne is suggested. The frequency-modulated autodyne signal at the harmonic vibrations of the reflector is theoretically described, and relationships for the autodyne signal spectral components are derived using expansions into Fourier and Bessel series. The respective experimental setup is considered, and measuring data for the nanovibration amplitudes of the reflector and the autodyne spectra are considered.     

Tamm States in Bragg Heterostructures on Waveguide Slot Lines

Tamm surface states are experimentally studied and calculated for a Bragg heterostructure consisting of two groups of periodic fragments of waveguide slot transmission line with finite sizes. The Tamm surface states are not observed in a perfect Bragg heterostructure. The Tamm surface states emerge in the presence of an interface element at the interface of two Bragg structures when the characteristics of the element differ from the characteristics of both Bragg structures.     

Analysis of elastic properties of a spherical shell using a semiconductor laser autodyne

The possibility of using a semiconductor laser autodyne for estimating the elastic properties of a spherical shell simulating the eyeball is investigated. Estimation is based on the determination of the parameters of motion of a segment of a spherical shell under the action of a pneumatic pulse. The results lead to the conclusion that the ratio of the deflection to the acceleration of the shell is a constant quantity weakly depending on the pressure of pneumatic pulses and on the distance between their source and the shell.